/*
Wotonomy: OpenStep design patterns for pure Java applications.
Copyright (C) 2000 Michael Powers

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, see http://www.gnu.org
*/

package net.wotonomy.datastore;

import java.util.List;
import java.util.Observer;

public interface DataView extends List {
//    public void newQuery( String aProperty, Object beginKey, Object endKey );
//    public void addQuery( String aProperty, Object beginKey, Object endKey );
//    public void removeQuery( String aProperty, Object beginKey, Object endKey );
//    public void retainQuery( String aProperty, Object beginKey, Object endKey );

	/**
	 * This method is called to notify the DataView that one of its objects has been
	 * modified and should be updated when the view is committed.
	 */
	public void update(Object o);

	/**
	 * This method is called commit all changes to the DataView to its data store.
	 * The list elements may be refreshed from the datastore, although the list
	 * itself should remain unchanged.
	 * 
	 * @return True if the commit was successful, otherwise false.
	 */
	public boolean commit();

	/**
	 * Called to add the specified observer to the list of observers that should
	 * receive notifications when the view if modified. DataViews notify when
	 * objects are added, updated, or deleted, passing the affected object as the
	 * parameter to the Observer's notify method.
	 * 
	 * @param o The observer to add.
	 */
	public void addObserver(Observer o);

	/**
	 * Called to remove the specified observer from the list of observers that
	 * should receive notifications when the view if modified.
	 * 
	 * @param o The observer to delete.
	 */
	public void deleteObserver(Observer o);

	/**
	 * Called to clear the list of observers that should receive notifications when
	 * the view if modified.
	 */
	public void deleteObservers();

	/**
	 * Returns the key for the specified object. If the object is not in the view,
	 * returns null.
	 */
	public DataKey getKeyForObject(Object anObject);

	/**
	 * Returns the object for the specified key. If the key is not in the view,
	 * returns null.
	 */
	public Object getObjectForKey(DataKey aKey);
}

/*
 * $Log$ Revision 1.2 2006/02/19 16:26:19 cgruber Move non-unit-test code to
 * tests project Fix up code to work with proper imports Fix maven dependencies.
 *
 * Revision 1.1 2006/02/16 13:18:56 cgruber Check in all sources in
 * eclipse-friendly maven-enabled packages.
 *
 * Revision 1.2 2001/02/15 21:12:41 mpowers Added accessors for key throughout
 * the api. This breaks compatibility. insertObject now returns the permanent
 * key for the newly created object. The old way returned a copy of the object
 * which was an additional read that was often ignored. Now you can read it only
 * if you need it. Furthermore, there was not other way of getting the permanent
 * key.
 *
 * Revision 1.1.1.1 2000/12/21 15:47:05 mpowers Contributing wotonomy.
 *
 * Revision 1.2 2000/12/20 16:25:36 michael Added log to all files.
 *
 *
 */